制膜基底对非溶剂致相转化法PVDF膜结构与性能的影响

摘要

以聚偏氟乙烯( PVDF)/N,N-二甲基乙酰胺-辛醇/水为制膜体系,采用干、湿相转化法制膜.考察了制膜基底对膜结构、表面浸润性和透过性能的影响.对膜样品的XRD测试表明,具有一定粗糙度的砂纸基底对液态膜具有粘附限制作用,在成膜过程中的液-固分相与液-液分相的竞争中占据更大优势.在适当粗糙度的砂纸基底上可以制得底面高度疏水且透过性能良好的PVDF微孔膜.%Polyvinylidene fluoride (PVDF) membrane were tailored by dry-wet phase inversion with the system of PVDF/N,N-dimethylacetamide and octanol/water. Effects of the substrate on the morphology, wettability and permeability of PVDF membrene were investigated. It was found that the membrane could be adhered to the abrasive paper, so that liquid-solid demixing was promoted and polymer crystallites had grown in all directions. It was confirmed by wide-angle X-ray scattering. A highly hydrophobic porous PVDF membrane with an enhanced permeability could be obtained by using a certain type of abrasive paper substrate.